Thermoelectric-enhanced, rack-level cooling of airflow entering an electronics rack is provided by a cooling apparatus, which includes: an air-to-liquid heat exchanger; a coolant loop coupled to the heat exchanger, the coolant loop including a first loop portion and a second loop portion, where the heat exchanger exhausts heated coolant to the first loop portion and receives cooled coolant from the second loop portion. The cooling apparatus further includes a heat rejection unit and a thermoelectric heat pump(s). The heat rejection unit is coupled to the coolant loop between the first and second loop portions, and provides partially-cooled coolant to the second loop portion. The thermoelectric heat pump is disposed with the first and second loop portions coupled to opposite sides to transfer heat from the partially-cooled coolant within the second loop portion to provide the cooled coolant before entering the air-to-liquid heat exchanger.